| 摘要 |
PURPOSE:To reduce cost and easily replace a temperature sensor by performing temperature compensation operation based on storage data when dispersious are found in forward voltage offset and temperature coefficient of the temperature sensor to be used. CONSTITUTION:The thermal media of temperature sensors 1 and 2 are arranged at flow-in and flow-out sides and a measurement temperature range according to the level of a detection temperature signal by the temperature sensors is selected. Then, the detection temperature signal according to the measurement of the measurement temperature range is amplified, and is converted to a digital signal and then the compensation value for temperature error is stored by a storage means 13. Then, by obtaining the difference between a value obtained by an A/D converter in the stored first setting temperature state and that obtained by an A/D converted on measurement, an offset error is compensated and the temperature error coefficient is compensated by the compensation value for the stored temperature coefficient error. Then, the temperatures at the flow-in and flow-out sides are calculated by an operation means 12, thus calculating the temperature difference between the flow-in and flow-out. |
